[unreadable] [unreadable] This proposal describes a 3-year study that will investigate the effectiveness of a Brief Intervention (BI) for high risk (non-dependent) use of illicit drugs as linked to the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST), a new instrument developed by the World Health Organization (WHO). The ASSIST was recently developed by an international group of researchers to screen for problem or risky use of tobacco, alcohol, cannabis, cocaine, amphetamines, sedatives, hallucinogens, inhalants, opiates and other drugs. The proposed study will allow US participation in an international multi-site collaborative project to evaluate the effectiveness of a brief intervention for four illicit drugs (cannabis, amphetamines, cocaine and opiates) as linked to the WHO ASSIST. The study will use a randomized controlled design in which eligible patients (N=160 non-dependent users of four illicit substances) presenting for care at a large dental clinic will be randomly assigned to either an experimental condition or a waitlist control group. Experimental subjects will receive a brief motivational intervention for the drug with the highest ASSIST severity score as well as self-help materials relating to that drug. Both groups will be re-assessed at three and six months with the ASSIST and related outcome measures. The project will be conducted independently at the University of Connecticut but will be linked to a larger multi-site study being sponsored by WHO at collaborating sites Australia, Brazil, the United Kingdom, India, and Thailand, where an additional 480 participants will be recruited. [unreadable] [unreadable]